Touch sensor and display device with touch sensor

ABSTRACT

First electrodes are formed on an insulation surface in such a manner that the adjacent first electrodes are connected in a first direction and are separated in a second direction intersecting the first direction. Second electrodes are formed on an insulation surface in such a manner that the adjacent second electrodes are connected in the second direction and are separated in the first direction. Third electrodes are formed in regions in which the third electrodes overlap with the first electrodes and do not overlap with the second electrodes in such a manner that the adjacent third electrodes are connected in the second direction and are separated in the first direction. A flexible insulation layer is formed between the first electrodes and the third electrodes. An area of each of the third electrodes is less than an area of each of the first electrodes.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a Continuation of U.S. application Ser. No.15/704,535 filed Sep. 14, 2017, and claims priority from Japaneseapplication JP2016-188089 filed on Sep. 27, 2016, the content of each ofwhich is hereby incorporated by reference into this application.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a touch sensor and a display devicewith the touch sensor.

2. Description of the Related Art

Electrostatic capacitance schemes are widely used for touch panels ofmobile displays of smartphones or the like. In the related art, touchpanels are formed separately from displays in many cases. However, inrecent years, touch panels tend to be contained because of thinness, lowcost, and superiority of optical characteristics.

As a sensing scheme, there known a display on which a pressure sensorwhich detects a position and also detects a pressing pressure whenpressing is performed with a finger mounted (JP2011-501307A). Since thepressure sensor is not transparent, the pressure sensor is located onthe rear of the display or a peripheral region (casing) of a displayregion separately from a touch position detection sensor so that lightemission is not hindered.

Japanese Patent No. 5783346 discloses a structure in which positiondetection electrodes and pressing pressure detection electrodes aredisposed to overlap each other. In this structure, since an electricfield is shielded by the pressing pressure detection electrode at thetime of detecting a position in an electrostatic capacitance scheme,there is a concern of a sensing operation of a touch position beinghindered.

SUMMARY OF THE INVENTION

An object of the invention is to detect a pressing pressure withouthindering sensing of a touch position.

According to an aspect of the invention, there is provided a touchsensor including: a plurality of first electrodes that are formed on aninsulation surface in such a manner that the adjacent first electrodesare disposed to be connected in a first direction and are disposed to beseparated in a second direction intersecting the first direction; aplurality of second electrodes that are formed on an insulation surfacein such a manner that the adjacent the second electrodes are disposed tobe connected in the second direction and are disposed to be separated inthe first direction; a plurality of third electrodes that are formed inregions in which the third electrodes overlap the plurality of firstelectrodes and do not overlap the plurality of second electrodes in sucha manner that the adjacent third electrodes are disposed to be connectedin the second direction and are disposed to be separated in the firstdirection; and a flexible insulation layer that is formed between theplurality of first electrodes and the plurality of third electrodes. Anarea of each of the plurality of third electrodes is less than an areaof each of the plurality of first electrodes.

According to the aspect of the invention, since the area of the thirdelectrode is less than the area of the first electrode, an electricfield generated between the first and second electrodes is notcompletely shielded by the third electrode. Accordingly, it is possibleto sense a touch position using the first and second electrodes and todetect a pressing pressure using the first and third electrodes.

According to another aspect of the invention, there is provided adisplay device with a touch sensor. The display device includes thetouch sensor; a substrate that has a display region in which a pluralityof pixels respectively including light-emitting elements are arrayed ina matrix form; and a sealing layer that covers the display region andfurther includes an inorganic insulation layer of at least one layer andan organic insulation layer of at least one layer. The touch sensor isabove the sealing layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a display device according toan embodiment of the invention.

FIG. 2 is an enlarged view illustrating a portion indicated by II inFIG. 1.

FIG. 3 is an enlarged view illustrating a partially omittedcross-section taken along the line of the display device illustrated inFIG. 2.

FIG. 4 is an enlarged view illustrating a cross-section taken along theline IV-IV of the display device illustrated in FIG. 2.

FIG. 5 is an enlarged view illustrating a cross-section taken along theline V-V of the display device illustrated in FIG. 2.

FIG. 6 is a diagram illustrating a circuit for touch sensing in thedisplay device according to the embodiment.

FIG. 7 is a diagram illustrating a touch sensing flow of the displaydevice according to the embodiment.

FIG. 8 is a diagram illustrating a state in which a screen is pressedwith a finger.

FIG. 9 is a diagram illustrating a circuit for pressing pressure sensingin the display device according to the embodiment.

FIG. 10 is a diagram illustrating a pressing pressure sensing flow ofthe display device according to the embodiment.

FIG. 11 is a diagram illustrating a result of a simulation performed toinspect an influence of shielding by a third electrode.

FIG. 12 is a diagram illustrating an area ratio of a first electrode tothe third electrode.

FIG. 13 is a diagram according to a first modification example of theembodiment of the invention.

FIG. 14 is a sectional view the structure taken along the line XIV-XIVillustrated in FIG. 13.

FIG. 15 is a diagram according to a second modification example of theembodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, embodiments of the invention will be described withreference to the drawings. Here, the invention can be embodied accordingto various aspects within the scope of the invention without departingfrom the gist of the invention and is not construed as being limited tocontent described in the embodiments exemplified below.

The drawings are further schematically illustrated in widths, thickness,shapes, and the like of units than actual forms to further clarifydescription in some cases, but are merely examples and do not limitinterpretation of the invention. In the present specification and thedrawings, the same reference numerals are given to elements having thesame functions described in the previously described drawings and therepeated description will be omitted.

Further, in the detailed description of the invention, “above” and“below” in definition of positional relations of certain constituentsand other constituents includes not only a case in which a constituentis located immediately above or immediately below a certain constituentbut also a case in which another constituent is interposed betweenconstituents unless otherwise mentioned.

FIG. 1 is a perspective view illustrating a display device according toan embodiment of the invention. An organic electroluminescence displaydevice will be exemplified as the display device. The display device isconfigured to display a full-color image by combining a plurality ofpixels (subpixels) of, for example, red, green, and blue and formingpixels of full color. The display device includes a first substrate 10.The first substrate 10 includes a display region DA in which a pluralityof pixels are arrayed in a matrix form. An integrated circuit chip 12driving elements to display an image is mounted on the first substrate10 and a flexible printed substrate (not illustrated) may be connectedto electrically connect the integrated circuit chip 12 to the outside.

FIG. 2 is an enlarged view illustrating a portion indicated by II inFIG. 1. FIG. 3 is an enlarged view illustrating a partially omittedcross-section taken along the line of the display device illustrated inFIG. 2. The first substrate 10 is formed of a resin or glass or may be afilm that has flexibility, such as polyimide or polyethyleneterephthalate. In the first substrate 10, an undercoat layer 14 servingas a barrier against impurities contained in the first substrate 10 isformed. The undercoat layer 14 is formed of a silicon oxide film or asilicon nitride film or may have a stacked structure of a silicon oxidefilm and the silicon nitride film. A semiconductor layer 16 is formedabove the undercoat layer 14. A source electrode 18 and a drainelectrode 20 are electrically connected to the semiconductor layer 16and a gate insulation film 22 is formed to cover the semiconductor layer16. A gate electrode 24 is formed above the gate insulation film 22 andan inter-layer insulation film 26 is formed to cover the gate electrode24. The source electrode 18 and the drain electrode 20 penetrate throughthe gate insulation film 22 and the inter-layer insulation film 26. Athin film transistor 28 is configured to include the semiconductor layer16, the source electrode 18, the drain electrode 20, and the gateelectrode 24. A passivation film 30 is formed to cover the thin filmtransistor 28.

A planarized layer 32 is formed above the passivation film 30. Above theplanarized film 32, a plurality of pixel electrodes 34 (for example, ananode) are formed to correspond to the plurality of unit pixels(subpixels), respectively. The planarized layer 32 is formed so thatsurfaces on which at least the pixel electrodes 34 are formed areplanarized. As the planarized layer 32, an organic material such as aphotosensitive acrylic resin is used in many cases. The pixel electrode34 is electrically connected to one of the source electrode 18 and thedrain electrode 20 above the semiconductor layer 16 by a contact hole 36penetrating through the planarized layer 32 and the passivation film 30.

An insulation layer 38 is formed above the planarized layer 32 and thepixel electrode 34. The insulation layer 38 is straddled on a peripheralportion of the pixel electrode 34 and is formed to open a part (forexample, a middle portion) of the pixel electrode 34. A bank surroundinga part of the pixel electrode 34 is formed by the insulation layer 38.

A light-emitting layer 40 is formed above the pixel electrode 34. Thelight-emitting layer 40 is formed independently (separated) for eachpixel electrode 34 and is also straddled on the insulation layer 38. Inthis case, the light-emitting layer 40 emits blue, red, or green lightto correspond to each pixel. The color corresponding to each pixel isnot limited thereto. For example, yellow or white may be added. Thelight-emitting layer 40 is formed by, for example, evaporation.Alternatively, the light-emitting layer 40 may be formed across theplurality of pixels on the entire surface covering the display region DA(see FIG. 1). That is, the light-emitting layer 40 is continuouslyformed above the insulation layer 38. In this case, the light-emittinglayer 40 is formed by coating in accordance with solvent dispersion. Ina case in which the light-emitting layer 40 is formed across theplurality of pixels, the light-emitting layer 40 has a configuration inwhich white is emitted in all of the subpixels and a portion with adesired color wavelength is extracted through a color filter (notillustrated).

A counter electrode 42 (a common electrode or an anode) is formed abovethe light-emitting layer 40. The counter electrode 42 is straddled onthe insulation layer 38 serving as a bank. A light-emitting element 44includes the light-emitting layer 40, and the pixel electrode 34 and thecounter electrode 42 interposing the light-emitting layer 40. Each ofthe plurality of pixels includes the light-emitting element 44. Thelight-emitting layer 40 is interposed between the pixel electrode 34 andthe counter electrode 42 and emits light in such a manner that itsluminance is controlled by a current flowing between the pixel electrode34 and the counter electrode 42. At least one layer of a hole transportlayer and a hole injection layer (neither of which is illustrated) maybe formed between the light-emitting layer 40 and the pixel electrode34. At least one layer of an electron transport layer and an electroninjection layer (neither of which is illustrated) may be formed betweenthe light-emitting layer 40 and the counter electrode 42.

The light-emitting element 44 is covered with a sealing layer 46 stackedon the counter electrode 42 to be sealed, and thus is blocked fromwater. The sealing layer 46 may have a stacked structure in which aninorganic insulation layer of at least one layer formed of SiN isfurther included. For example, as illustrated in FIG. 3, the sealinglayer 46 may have a structure in which an organic insulation layer 52 ofat least one layer formed of a resin or the like is interposed between apair of inorganic insulation layers 48 and 50. The sealing layer 46covers the display region DA (see FIG. 1).

The display device according to the embodiment includes a touch sensor54 above the sealing layer 46. The touch sensor 54 includes a pluralityof first electrodes 56. The plurality of first electrodes 56 are formedabove an insulation surface 84 of the sealing layer 46. In the pluralityof first electrodes 56, the first electrodes 56 adjacent in the firstdirection D1 are disposed to be connected (in which details will bedescribed below) and the first electrodes 56 adjacent in the seconddirection D2 intersecting (for example, orthogonal to) the firstdirection D1 are disposed to be separated.

As illustrated in FIG. 3, a region (space) between the adjacent firstelectrodes 56 is located on the upper side of the insulation layer 38(the bank). Each first electrode 56 has a size covering a plurality ofpixels. In a case in which a distance between the first electrode 56 andthe light-emitting element 44 is close, optical characteristics areimproved by causing the shape of the first electrode 56 to correspond tothe shape of the pixel. When the first electrode 56 and thelight-emitting element 44 are sufficiently separated from each other, itis not necessary to form the first electrode 56 according to the shapeof the pixel. The content described in this paragraph also correspondsto the second electrode 58 to be described below.

The touch sensor 54 includes the plurality of second electrodes 58, asillustrated in FIG. 2. The plurality of second electrodes 58 are formedon the insulation surface 84 of the sealing layer 46 (see FIG. 3). Inthe plurality of second electrodes 58, the second electrodes 58 adjacentin the second direction D2 are disposed to be connected and the secondelectrodes 58 adjacent in the first direction D1 are disposed to beseparated. The second electrodes 58 adjacent in the second direction D2are connected by a second connection portion 60. The second electrodes58 and the second connection portion 60 are disposed in the same layer.The plurality of first electrodes 56 and the plurality of secondelectrodes 58 are disposed in the same layer without overlapping eachother and are spaced to be insulated from each other.

FIGS. 4 and 5 are enlarged views illustrating cross-sections taken alongthe lines IV-IV and V-V of the display device illustrated in FIG. 2,respectively. The adjacent first electrodes 56 are connected by a firstconnection portion 62. The first connection portion 62 overlap thesecond connection portion 60, but are configured not to be conductivevia an insulation film 64. In FIGS. 4 and 5, the insulation film 64 isdisposed only immediately below the first connection portion 62 and isseparated into a plurality of portions. The insulation film 64 is formedto entirely cover the first electrode 56 and a contact hole may beopened only in a connection portion of the first connection portion 62and the first electrode 56.

The touch sensor 54 includes a plurality of third electrodes 66, asillustrated in FIG. 2. The plurality of third electrodes 66 overlap theplurality of first electrodes 56. A flexible insulation layer 90 isformed between the plurality of first electrodes 56 and the plurality ofthird electrodes 66. The flexible insulation layer 90 is continuouslyformed from a plurality of first region overlapping the plurality offirst electrodes 56 to a plurality of second regions overlapping theplurality of second electrodes 58. The flexible insulation layer 90 caneasily be formed such as aqueous dispersion polyurethane and ispreferably formed of a transparent soft material.

As illustrated in FIG. 2, the plurality of third electrodes 66 overlapnone of the plurality of second electrodes 58. The plurality of thirdelectrodes 66 are disposed so that the adjacent third electrodes 66 areseparated in the first direction D1. The plurality of third electrodes66 are disposed so that the adjacent third electrodes 66 are connectedin the second direction D2. The third electrodes 66 adjacent in thesecond direction D2 are connected by a third connection portion 68. Thethird electrodes 66 and the third connection portion 68 are disposed inthe same layer. The first electrode 56, the second electrode 58, and thethird electrode 66 are formed of a material which can be transparentlyformed at a low temperature, such as indium tin oxide (ITO) or indiumzinc oxide (IZO).

As illustrated in FIG. 3, a second substrate 70 is adhered to theplurality of third electrodes 66 in the uppermost layer of the touchsensor 54. The second substrate 70 is formed of a resin or glass and maybe a film that has flexibility as in the first substrate 10. An adhesive(not illustrated) is used when the second substrate 70 is adhered. Thedisplay device can contain a touch panel, and thus is configured todetect a touch by approach to a conductor such as a finger. In theembodiment, the principle of a mutual capacitance scheme adopted. In themutual capacitance scheme, presence or absence of a touch andcoordinates of the touch are determined by detecting a change inelectrostatic capacitance between the plurality of first electrodes 56and the plurality of second electrodes 58.

FIG. 6 is a diagram illustrating a circuit for touch sensing in thedisplay device according to the embodiment. The display device includesa sensing circuit 72. For example, the sensing circuit 72 is containedin the integrated circuit chip 12 illustrated in FIG. 1. The sensingcircuit 72 includes a first selection circuit 74. The first selectioncircuit 74 selects one group of the first electrodes 56 connected in thefirst direction D1. The sensing circuit 72 includes a second selectioncircuit 76. The second selection circuit 76 selects one group of thesecond electrodes 58 connected in the second direction D2. The sensingcircuit 72 includes a pulse generator 78. A pulse voltage output fromthe pulse generator 78 is applied to one of the selected one group ofthe first electrodes 56 and the selected one group of the secondelectrodes 58 (in this example, the former). Other electrodes (in thisexample, the second electrodes 58) different from to the electrodes towhich the pulse voltage is applied are connected to an ammeter 80. Theammeter 80 measures a first physical amount (current value)corresponding to first electrostatic capacitance. The first physicalamount corresponds to electrostatic capacitance between one group of thefirst electrodes 56 and one group of the second electrodes 58.

The electrostatic capacitance is formed between one group of the firstelectrodes 56 connected in the first direction D1 and one group of thesecond electrodes 58 connected in the second direction D2. For example,first electrostatic capacitance is formed between the selected one groupof the first electrodes 56 and the selected one group of the secondelectrodes 58. When a pulse is input to one of the first electrode 56and the second electrode 58, a potential variation is delivered to theother of the first electrode 56 and the second electrode 58 by couplingbased on the first electrostatic capacitance. When there is a touch of aconductor such as a finger, an electric field is also generated betweenthe touched conductor and the first electrode 56 or between the touchedconductor and the second electrode 58 in addition to an electric fieldbetween the first electrode 56 and the second electrode 58. Theseelectric fields inhibit a part of the coupling between the firstelectrode 56 and the second electrode 58. Accordingly, at a touchedlocation, the delivery of the potential variation between the firstelectrode 56 and the second electrode 58 by the coupling decreases. Bydetecting this change amount (see the next paragraph), presence orabsence of the touch and the coordinates of the touch are detected.

FIG. 7 is a diagram illustrating a touch sensing flow of the displaydevice according to the embodiment. When the first physical amount(current value) is measured by the ammeter 80 illustrated in FIG. 6(S11), a first measurement value obtained through the measurement isinput to a determination circuit 82. The determination circuit 82determines whether the first measurement value deviates from a firstrange. The first range is a range in which an error is considered in adesigned value when there is no touch of the conductor such as a finger.When the first measurement value is within the first range, there is notouch. When the first measurement value deviates from the first range,it is detected that a meaningful change in the first electrostaticcapacitance is made due to approach of the conductor such as a finger(that is, there is a touch).

In the embodiment, the mutual capacitance scheme in which the firstmeasurement value is lowered when there is a touch is adopted.Therefore, the determination circuit 82 determines whether the firstmeasurement value is less than a first predetermined value bydetermining whether the first measurement value deviates from the firstrange (S12). When the result of the determination is NO, it is detectedthat there is no touch (S13). When the result of the determination isYES, it is detected that there is the touch (S14).

FIG. 8 is a diagram illustrating a state in which a screen is pressedwith a finger. The flexible insulation layer 90 is pressed via thesecond substrate 70 and the third electrode 66 by a pressing pressure.Thus, a gap between the first electrode 56 and the third electrode 66 isnarrowed. As a result, the electrostatic capacitance between the firstelectrode 56 and the third electrode 66 increases. In the embodiment,the pressing pressure of a touch is determined by detecting a change inthe electrostatic capacitance between the plurality of first electrodes56 and the plurality of third electrodes 66 caused by a displacement ofthe flexible insulation layer 90 in its thickness direction.

FIG. 9 is a diagram illustrating a circuit for pressing pressure sensingin the display device according to the embodiment. The sensing circuit72 measures second physical amount corresponding to a secondelectrostatic capacitance between each of the plurality of firstelectrodes 56 and each of the plurality of third electrodes 66. Whenonly presence or absence of a pressing pressure is detected (a positionof the pressing pressure not is detected), the second physical amountcorresponding to a sum of the plurality of second electrostaticcapacitances may be measured. For example, the plurality of firstelectrodes 56 are connected to each other, the plurality of thirdelectrodes 66 are connected to each other, the second physical amount(current value) is measured by the ammeter 80 in accordance with a pulsevoltage applied from the pulse generator 78. The plurality of firstelectrodes 56 may be connected to each other by the first selectioncircuit 74 (see FIG. 6) and the plurality of third electrodes 66 may beconnected to each other by the second selection circuit 76 (see FIG. 6).When there is a pressing pressure by a finger or the like, secondelectrostatic capacitance increases. Accordingly, current consumptionincreases when the pulse generator 78 inputs a pulse to the plurality offirst electrodes 56 or the plurality of third electrodes 66 to performcharging or discharging.

FIG. 10 is a diagram illustrating a pressing pressure sensing flow ofthe display device according to the embodiment. When the second physicalamount (current value) is measured by the ammeter 80 (S21), a secondmeasurement value obtained through the measurement is input to thedetermination circuit 82 (see FIG. 9). The determination circuit 82determines whether the second measurement value deviates from a secondrange. The second range is a range in which an error is considered in adesigned value when there is no pressing pressure by a finger or thelike. When the second measurement value is within the second range,there is no pressing pressure. When the second measurement valuedeviates from the second range, it is detected that a meaningful changein the second electrostatic capacitance is made due to compression ofthe flexible insulation layer 90 by a pressing pressure force (that is,there is a pressing pressure).

When the flexible insulation layer 90 is compressed, the gap between thefirst electrode 56 and the third electrode 66 is narrowed and the secondmeasurement value increases. Therefore, the determination circuit 82determines whether the second measurement value is greater than a secondpredetermined value by determining whether the second measurement valuedeviates from the second range (S22). When the result of thedetermination is NO, it is detected that there is no pressing pressure(S23). When the result of the determination is YES, it is detected thatthere is the pressing pressure (S24).

According to the embodiment, as illustrated in FIG. 2, the area of eachof the plurality of third electrodes 66 is less than the area of each ofthe plurality of first electrodes 56. Accordingly, an electric fieldgenerated between the first electrode 56 and the second electrode 58 atthe time of touch sensing is not completely shielded by the thirdelectrode 66. Therefore, the touch sensing can be performed using thefirst electrode 56 and the second electrode 58. In addition, thepressing pressure sensing can be performed using the first electrode 56and the third electrode 66.

FIG. 11 is a graph illustrating a result of a simulation performed toinspect an influence of shielding by the third electrode 66.Specifically, when a pulse voltage is applied to the first electrode 56overlapped below the third electrode 66, it was calculated how theelectrostatic capacitance between the first electrode 56 and a finger(not illustrated) changes according to an area ratio of the thirdelectrode 66 to the first electrode 56. In FIG. 11, the horizontal axisrepresents an area ratio of the third electrode 66 to the firstelectrode 56 and the vertical axis represents a ratio of theelectrostatic capacitance. When the area ratio is 0%, there is no thirdelectrode 66. At that time, the electrostatic capacitance is assumed tobe 100%. In other words, an inhibition ratio of the electrostaticcapacitance between the first electrode 56 and the finger is assumed tobe 0%.

To cause a position sensing function by the first electrode 56 and thesecond electrode 58 and a pressure-sensitive sensing function by thefirst electrode 56 and the third electrode 66 to be compatible, it isnecessary to ensure electrostatic capacitance of at least 50% in thissimulation. When the area ratio is 65%, the electrostatic capacitance is50%. In other words, when the area ratio of the third electrode to thefirst electrode 56 is 65%, 50% of the electrostatic capacitance betweenthe first electrode 56 and the finger is inhibited by the thirdelectrode 66. Accordingly, the area of each of the plurality of thirdelectrodes 66 is preferably equal to or less than 65% of the area ofeach of the plurality of first electrodes 56. Further, 25% at which theelectrostatic capacitance of 90% is obtained may be set as a lower limitof the area ratio.

FIG. 12 is a diagram illustrating an area ratio of the first electrode56 to the third electrode 66. In this example, the first electrode 56has a diamond pattern. For example, when a width W1 of a side of thefirst electrode 56 is 4 mm, the area is 16 mm². The area of the thirdelectrode 66 may be equal to or less than 10.4 mm² which is 65% of thearea or a width W3 of a side of the third electrode 66 may be equal toor less than 3.2 mm.

FIG. 13 is a diagram according to a first modification example of theembodiment of the invention. FIG. 14 is a sectional view the structuretaken along the line XIV-XIV illustrated in FIG. 13. In this example,first electrodes 156 and second electrodes 158 are arranged on aninsulation surface 184. A flexible insulation layer 190 is provided tobe separated from a plurality of first regions A1 overlapping theplurality of first electrodes 156 and a second region A2 different fromthe plurality of first regions A1. Third electrodes 166 are disposed onthe upper side of the first electrodes 156 and above the flexibleinsulation layer 190. In this example, since the flexible insulationlayer 190 is separated from the first regions A1 and the second regionA2, the flexible insulation layer 190 is easily deformed. Since theflexible insulation layer 190 is considerably changed, a change inelectrostatic capacitance increases and sensitivity of a pressingpressure sensing is raised.

FIG. 15 is a diagram according to a second modification example of theembodiment of the invention. In this example, a buffer layer 286 isinterposed between a third electrode 266 and a flexible insulation layer290. The buffer layer 286 is formed of a material that has tolerance tochemicals used for photolithography or etching. For example, a siliconnitride film formed by a chemical vapor deposition (CVD) process can beexemplified.

Since there is the buffer layer 286, it is possible to protect theflexible insulation layer 290 against chemicals when the thirdelectrodes 266 are formed above the buffer layer 286 by photolithographyor etching. A contact hole (not illustrated) for electric connection ofthe third electrodes 266 is formed by etching the flexible insulationlayer 290 along with the buffer layer 286. In a case in which chemicalresistance of the flexible insulation layer 290 is excellent as in afluorine-based resin or when a process of forming the third electrode266 is a process in which a large amount of chemicals such as ink jet isnot used, the buffer layer 286 is unnecessary.

The display device is not limited to an organic electroluminescencedisplay device, but a display device in which each pixel includes alight-emitting element such as a quantum-dot light emitting diode (QLED)or a liquid crystal display device may be used. The touch sensor is notlimited to the mutual capacitance scheme, but may be a self-capacitancescheme.

While there have been described what are at present considered to becertain embodiments of the invention, it will be understood that variousmodifications may be made thereto, and it is intended that the appendedclaims cover all such modifications as fall within the true spirit andscope of the invention.

What is claimed is:
 1. A display device with a touch sensor, comprising:a substrate including a display region with a plurality of pixels; afirst insulation layer on the plurality of pixels; a plurality of firstelectrodes on the first insulation layer; a plurality of secondelectrodes on the first insulation layer; a second insulation layer onthe plurality of first electrodes and the plurality of secondelectrodes; and a plurality of third electrodes on the second insulationlayer; wherein an adjacent pair of the plurality of first electrodes areconnected with a first connection portion in a first direction, anadjacent pair of the plurality of second electrodes are connected with asecond connection portion in a second direction, an adjacent pair of theplurality of third electrodes are connected with a third connectionportion in the second direction, and the first connection portion andthe second connection portion intersect each other.
 2. The displaydevice with the touch sensor according to claim 1, wherein light passesthrough the first insulation layer and the second insulation layer todisplay an image.
 3. The display device with the touch sensor accordingto claim 1, wherein each of the plurality of first electrodes and acorresponding one of the plurality of third electrodes are overlapped ina plan view.
 4. The display device with the touch sensor according toclaim 1, wherein a side of each of the plurality of second electrodesand a side of a corresponding one of the plurality of third electrodesare opposed to each other side by side without overlapping of theplurality of second electrodes and the plurality of third electrodes ina plan view.
 5. The display device with the touch sensor according toclaim 1, wherein the second insulation layer is flexible.
 6. The displaydevice with the touch sensor according to claim 4, wherein the secondinsulation layer includes transparent soft material.
 7. The displaydevice with the touch sensor according to claim 1, wherein the secondinsulation layer continuously includes a plurality of first regionsoverlapping with the plurality of first electrodes and a plurality ofsecond regions overlapping with the plurality of second electrodes. 8.The display device with the touch sensor according to claim 1, whereinthe second insulation layer is formed to be separated into a pluralityof first regions overlapping with the plurality of first electrodes anda second region different from the plurality first regions.
 9. Thedisplay device with the touch sensor according to claim 1, whereinpresence or absence of a touch and coordinates of the touch aredetermined by detecting a change in electrostatic capacitance betweenthe plurality of first electrodes and the plurality of secondelectrodes, and a pressing pressure of a touch is determined bydetecting a change in electrostatic capacitance between the plurality offirst electrodes and the plurality of third electrodes by displacementin a film thickness direction of the second insulation layer.
 10. Atouch sensor comprising: a plurality of first electrodes; a plurality ofsecond electrodes; a plurality of third electrodes; and an insulationlayer; wherein an adjacent pair of the plurality of first electrodes areconnected with a first connection portion in a first direction, anadjacent pair of the plurality of second electrodes are connected with asecond connection portion in a second direction, an adjacent pair of theplurality of third electrodes are connected with a third connectionportion in the second direction, the insulation layer is between theplurality of first electrodes and the plurality of third electrodes, theinsulation layer is between the plurality of second electrodes and theplurality of the third electrodes, and the first connection portion andthe second connection portion intersect each other.
 11. The touch sensoraccording to claim 10, wherein the insulation layer is directly on asurface of the plurality of first electrodes.
 12. The touch sensoraccording to claim 11, wherein the insulation layer is directly on asurface of the plurality of second electrodes.
 13. The touch sensoraccording to claim 10, wherein each of the plurality of first electrodesand a corresponding one of the plurality of third electrodes areoverlapped in a plan view.
 14. The touch sensor according to claim 10,wherein a side of each of the plurality of second electrodes and a sideof a corresponding one of the plurality of third electrodes are opposedto each other side by side without overlapping of the plurality ofsecond electrodes and the plurality of third electrodes in a plan view.15. The touch sensor according to claim 10, wherein the insulation layeris flexible.
 16. The touch sensor according to claim 15, wherein theinsulation layer includes soft material.
 17. The touch sensor accordingto claim 10, wherein the insulation layer continuously includes aplurality of first regions overlapping with the plurality of firstelectrodes and a plurality of second regions overlapping with theplurality of second electrodes.
 18. The touch sensor according to claim10, wherein the insulation layer is formed to be separated into aplurality of first regions overlapping with the plurality of firstelectrodes and a second region different from the plurality firstregions.
 19. The touch sensor according to claim 10, wherein presence orabsence of a touch and coordinates of the touch are determined bydetecting a change in electrostatic capacitance between the plurality offirst electrodes and the plurality of second electrodes, and a pressingpressure of a touch is determined by detecting a change in electrostaticcapacitance between the plurality of first electrodes and the pluralityof third electrodes by displacement in a film thickness direction of theinsulation layer.